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TLS Online TPP Program

#Question id: 5220

In comparing the genomes of humans and those of other higher primates, it is seen that humans have a large metacentric pair we call chromosome #2 among our 46 chromosomes, while the other primates of this group have 48 chromosomes and any pair like the human #2 pair is not present; instead the primate groups each have two pairs of midsize acrocentric chromosomes. What is the most likely explanation?

#SCPH06 I Botany

  1. The ancestral organism had 48 chromosomes and at some point a centric fusion event occurred and provided some selective advantage.

  2. The ancestral organism had 46 chromosomes, but primates evolved when one of the pairs broke in half.

  3. At some point in evolution, human ancestors and primate ancestors were able to mate and produce fertile offspring, making a new species.

  4. Chromosome breakage results in additional centromeres being made in order for meiosis to proceed successfully.

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TLS Online TPP Program

#Question id: 15636

#SCPH01 Biochemistry

While analysing motif sequences, what is the major disadvantageous feature of PROSITE?
TLS Online TPP Program

#Question id: 15636

#I Life Science/ Life Sciences Group – I-V

While analysing motif sequences, what is the major disadvantageous feature of PROSITE?
TLS Online TPP Program

#Question id: 15636

#SCPH05 I Biotechnology

While analysing motif sequences, what is the major disadvantageous feature of PROSITE?
TLS Online TPP Program

#Question id: 15636

#SCPH05 I Biotechnology

While analysing motif sequences, what is the major disadvantageous feature of PROSITE?
TLS Online TPP Program

#Question id: 15637

#SCPH01 Biochemistry

You have isolated two mutations in the Lac operon that cause constitutive expression of Lac genes. You designate these mutants Lac1– and Lac2–. Making use of an F' that carries the Lac operon with the LacY gene mutated, you construct strains that you test for both ß-galactosidase activity and Lac permease activity with results shown below.
     
Classify each mutation as dominant or recessive and as cis- or trans-acting, giving the experimental result that allows you to arrive at each conclusion. Finally, deduce what type of Lac mutation best fits the properties of Lac 1– and of Lac 2–.
TLS Online TPP Program

#Question id: 15637

#SCPH06 I Botany

You have isolated two mutations in the Lac operon that cause constitutive expression of Lac genes. You designate these mutants Lac1– and Lac2–. Making use of an F' that carries the Lac operon with the LacY gene mutated, you construct strains that you test for both ß-galactosidase activity and Lac permease activity with results shown below.
     
Classify each mutation as dominant or recessive and as cis- or trans-acting, giving the experimental result that allows you to arrive at each conclusion. Finally, deduce what type of Lac mutation best fits the properties of Lac 1– and of Lac 2–.